They have made sure to keep their income in pace with the cost of living, but not the income of most people in this country. Many of them have other sources of income anyway. That or reduce it to the old level of nothing due to it being a public service.
Reducing their pay to either of these suggests will save a lot of money, further allowing for a smaller government. Therefore it works for people in all parties.
Then they will have a more fair opinion of what minimum wage should be set to.